VAR was again under scrutiny after Cesar Azpilicueta questioned why the pitch-side monitor was not used after he was hauled down by Harry Maguire.
But the Blues will feel aggrieved they were not awarded a first-half penalty.
Maguire was seen with his arms around Azpilicueta’s neck as the ball was flighted in, yet it went unpunished.
The Spaniard felt the decision could’ve gone either way but was surprised that referee Martin Atkinson didn’t take a moment to review the decision.
“A good question,” said the Chelsea star when asked whether he was fouled. “On the pitch I felt yes and I felt arms around my neck and shoulders.
“The referee can make the decision, the VAR is there [to help]. In any situation the referee takes the main decisions and the monitor is there for him to help.
“It was 50-50 so why not take 20 seconds to review it? I think VAR can improve a lot. It happens, it is football, I don’t say every time there is contact there should be a penalty.
“In England there is strong physical contact. In football and in the Premier League always we should seek improvement – it is not a criticism, we can all help together to make a better league.”
Azpilicueta was part of a Blues backline that kept just a second Premier League clean sheet of the season.
He played alongside Thiago Silva and Andreas Christensen in a three-man defence that kept United’s forwards relatively quiet.
The Blues though offered little going forward themselves and Azpilicueta felt as if they could’ve shown more attacking intent.
“I have the feeling we could have done more,” he confessed.
“We found spaces but we didn’t create the last pass or pick the right pass or make the right decisions.
“We defended solid and they have at the end one save by Edouard [Mendy] and in the first half one mistake by us, but we could do more.
“For moments we had spells. In the first half we controlled better but in the second half sometimes we rushed it and didn’t move the ball good enough.
“We lost possession too easily which meant we lost some control but we showed solidity and it was a great effort from everybody. Obviously we want more.”
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